We proposed to study the biochemical processes involved in the molecular modification and intracellular transport of beta-glucuronidase. The mouse kidney, in which the enzyme can be specifically induced by androgenic hormones, will be used as our experimental system. Electrophoresis, isoelectric focusing and enzyme digest ions will be used to study the molecular nature and interrelationship among various beta-glucuronidase isozymes of the lysosomes, microsomes and Golgi-apparatus. Subcellular and submicrosomal fractions then will be isolated to study the flow and distribution of beta glucuronidase through the subcellular organelles. This will be carried out by following the flow of the radioactively labelled beta-glucuronidase at various times after the pulse-labelling. The modification of the isozymes during the transport will be studied by following the flow of the labelled beta-glucuronidase through various electrophoretically separated isozyme components. Attempts will be made to develop a sensitive and specific immunocytochemical technique to study the localization of this enzyme at ultrastructural level. The observation from the cytochemical study can then be used to verify the biochemical findings on the transport and distribution of this enzyme. This study not only has potential significance to the understanding of the processes involved in the formation of lysosomes, but also is important for the understanding of mechanisms of the biosynthesis and transport of glycoproteins, which contribute greatly to the properties of the cell surface. The information gained from this study will also be of value for the studies of the molecular pathology of lysosomal diseases and the possible correlation of beta-glucuronidase to cancer.